Manifold attachment for internal combustion engines



April 23, 1935. DOERING 1,998,494

MANIFOLD ATTACHMENT FOR INTERNAL COMBUSTION ENGINES Filed Sept. 2, 1931 2 Sheets-Sheet 1 April 23, 1935. DQERING 1,998,494

MANIFOLD ATTACHMENT FOR INTERNAL COMBUSTION ENGINES F-iled Sept. 2, 1951 2 Sheets-Sheet 2 Patented Apr. 23, 1935 UNITED STATES PATENT OFFICE MANIFOLD ATTACHIHENT FOR INTERNAL COMBUSTION ENGINES 14 Claims.

This invention relates to fuel systems for internal combustion motors, and has for an object the provision of a manifold attachment adapted to establish communication between the interior of the manifold of such a motor, and the atmosphere when the supply of fuel to the motor has been cut off, and during the period of deceleration of the motor to idling speed. The device of the present invention constitutes an improvement over the devices forming the subjects matter of my copending applications, Serial No. 422,331, filed January 21, 1930, now Patent No. 1,923,357, and Serial No. 452,285, filed May 14, 1930, now Patent No. 1,895,789.

In order to facilitate understanding the construction and operation of the device of the present invention, without necessitating reference to my aforesaid copending applications, it should be explained herein that when the supply of fuel from the carburetor to the intake manifold of an internal combustion engine is suddenly and either completely or partially cut off, the motor continues to operate for a material length of time under the momentum of its rotating parts, gradually decreasing its speed until the motor is operating at idling speed, or at the speed which will be maintained by the decreased supply of fuel. During this period of deceleration the motor develops a. pumping action, due to the reciprocation of its pistons and the accompanying action of its valves, whereby a very high vacuum is developed within the intake manifold. Moreover, the butterfiy valve of the carburetor is incapable of sealing the throat of the carburetor, with the result that during the period of deceleration the jet or jets of the carburetor are subjected to the high vacuum which obtains within the manifold, causing raw or liquid fuel to be drawn through the jets, and by way of the manifold, into the cylinders of the motor. The fuel thus drawn into the cylinders is exceedingly rich, in fact it is too rich to ignite, with the result that it is expelled through the exhaust manifold in the form of a cloud of noxious gases and vapors, which not only are exceedingly objectionable, but which also tend to increase the cost of operation of the motor because of this wastage of fuel. The device of the present invention is designed to take care of this undesirable condition by automatically establishing communication between the interior of the intake manifold and the atmosphere during the period of deceleration of the motor, and thereby relieving the high vacuum which otherwise would obtain therein.

Another object is to provide an auxiliary air ,in the auxiliary air inlet valve inlet as described, adapted to be controlled by an electromagnetic device which is energized by the closing of a switch which accompanies the closing movement of the butterfly valve of the carburetor. 6

Another object is to provide an auxiliary air inlet of the general character indicated, whereis moved both to and from its open position by air pressure exerted in opposite directions against a piston when the opposite .end of the pistons cylinder is connected to the inlet manifold, thereby utilizing the vacuum within the manifold to cause movement of the auxiliary air inlet valve in both directions.

Another object is to provide means for automatically cutting oif the ignition of the motor when the auxiliary air inlet valve is open.

I A still further object is to provide means for cutting oif the supply of idling fuel from the carburetor to the manifold when the auxiliary valve is open.

A still further .object is to provide means for automatically resetting the various parts of the manifold attachment as soon as the period of deceleration of the motor is over, thereby permitting the motor to operate at idling speed.

The invention possesses other objects and advantageous features, some of which, with those enumerated, will be set forth in the following description of the inventions particular embodiments which are illustrated in the drawings accompanying and forming a part of the specification.

Referring to the drawings:

Fig. 1 is a view in side elevation of a motor showing the manner of connecting thereto a carburetor and a manifold attachment embodying the principles of the present invention.

Fig. 2 is a transverse vertical sectional view of my improved carburetor attachment. The plane of sectionis indicated by the line 2-2 of Fig. 1, and the direction of view by the arrows.

Fig. 3 is a top plan view of the carburetor attachment, the direction of view being indicated by the arrow 3 of Fig. 2.

Fig. 4 is a horizontal sectional view taken upon the line 4-4 of Fig. 2, with the directlonof view as indicated.

Fig. 5 is .a compound horizontal sectional view taken upon the lines 5-5 of Fig. 2, with the direction of view as indicated.

Fig. 6 is a diagrammatic view showing the electrical connections of the manifold attachment.

gage a fixed contact 2| when the butterfly valve communicates therewith through a different opening. i. e., the respective entrances of the manifold attachment H and the carburetor-l4 'are independent of each other. In accordance with conventional practice, the carburetor l4 isv provided with a butterfly valve l6-which is controlled by a lever l1 connected by any suitable operating mechanism ,l 6 to the throttle and ac- -celerator'pedal within the-operator's compart merit of the vehicle with which the motor I3 is associated. The parts are so arranged that the butterfly valve l6, i. e., thefmain' fuel supply valve of the carburetor I4, is opened by swinging the lever I1 inacounterclockwise direction, as viewed upon Fig. v1, from the'position in which it is illustrated upon that figure. The lever l1.

isconnected to a switch arm I! adapted to enl6 is closed. These contacts I! and 2| constitute a switch 22' for controlling the circuit whereby the manifold attachment II is operated, it being understood thatthis switch 22 is adapted to, be closed when the butterfly valve I6 is closed.

The manifold attachment H comprises a hous-' ing 26 having. a passage 21 therethrough terminating in a flange 26 whereby the housing 26 may be mounted upon the manifold l2 with the passage 21 communicating at one end with .the'

interior of the manifold. The other end 23 'of the passage 21 communicateswith the atmosphere, and preferably is provided with an air cleaner 3| the form of a cylindrical housing 32 having an opening 33 at the-bottom, whereby air may enterthe housing 32. Within the housing 32 a cylinder 34 is disposed. This cylinder is closed at the bottom as by'a plate 36, and comv prises spaced inner and outer shells 31 and 34,

respectively, each of which is composed of suit-. able foraminous material such as perforated, cylindrical plates or relatively coarse wire mesh.

Between the two, shells 31 and 36 a plurality of layers 44' of relatively fine wire mesh are provided, and the bore 39 of the inner shell 31 com-.

municates with the outer end 29 of the passage 21, with the result that all air entering the pas-. sage 21 must'first pass through the plurality of layers 40 of relatively fine mesh. The outside area of the cylinder 34 is considerably greater than the cross sectional area of the passage 21, with the result that the air passing throughthe mesh moves relatively slowly, with the result that dust and the like, which would otherwise be car-' ried into the intake manifold and thence into the cylinders of themotor l3, will be strained out of the-air by the mesh.

A horizontal valve seat 4| is so arranged with in the passage 21 that all air passing there-' through must pass through the valve seat 4|. A valve 42 is so associated with the valve seat 4| that it is adapted to seal the passage 21 by mov-' ing upwards onto the seat 4|, but is adapted to permit unrestricted passage of air into the manifold l2 by moving downwards from the seat. The stem 43 of the valve 42 extends slidablythrough a guide 44 and into a cylinder 46 arranged above that portion of the passage 21 which is adjacent the valve seat 4l.- -Within the cylinder 46 a piston 41 is reciprocable, this piston being threadedly or otherwise rigidly engaged with the stem 43 of the valve 42. A coil spring 48 is under compression between the bottom of the cylinder 46 and the under surface of the piston 41, with the result that the spring continually urges the piston 41 in that direction which will result in seating the valve 42.

The housing 5| within which the cylinder 46 is formed isalso provided with a valve chamber '52 having a slide valve 53 reciprocable therein. Preferably, the valve 53 is cylindrical and has. a

relatively wide annular groove 54 therein. The valve chamber 52has upper, middle and lower ports 56, 51 and 56, respectively, and the annular groove 54 of the valve 53 is adapted to establish communication optionally between the middle port 51 and the upper port 56, or with the middle port 51 and the lower port 58, by moving the valve 53 to its upper or lower extreme of move- ,ment, respectively.- The valve is illustrated upon Fig. 2 in its uppermost position wherein communication is established between the middle port 51 and the upper'port 56. The upper port 56 communicates by a passage 6! with the cylinder 46 above the piston 41, whereas the lower port 58 communicates by a passage 62 with the cylinder 46 below the piston 41, but through perforations 63 in the wall of the cylinder 46.

The uppermost perforations 63 are either larger or are of a greater'number than the lowerperforations 63, with the result that as the piston 41 approaches its lower extreme of movementit will cut oil the major connection between the lower end of the cylinder 46 and the passage 62, the

purpose being to decrease the speed at which the piston 41 is traveling when it reaches its lower extreme of movement.

v I prefer that an annular pad 64 of felt or similar material bejprovided in the lower end of the cylinder 46 encircling the stem 43. This pad not only serves as a cushion to prevent the piston 41- from coming forcibly into engagement with the lower end of the cylinder, but it also serves as a reservoir for lubricant for the 'walls of the cylinder 46.; This lubricant is absorbed by the pad 64, but a portion of the lubricant is squeezed therefrom when the piston 41 engages the upper surface of the pad, withthe result that some. of the lubricant will be forced between the piston and the cylinder walls and will be carried upwards and thus distributed over the remaining portion of the cylinder'walls upon the return stroke 'of the piston. Oil may be supplied to the interior of the'cylinder 46 by removing a threaded plug 65' preferably in the upper end of the cylinder.

The middle port 51 communicates with a passage 66: which leads to the outside of the housing 5| preferably by way of a threaded nipple 61, to which a'tube 66 (see Fig. 1) may be connected. This tube 66 leads from the nipple 61 to the passage 21 below the valve seat 4|, with the result that the same pressure which exists within the manifold l2 will at all times obtain within the passage 66 and middle port 51.

The slide valve 53 is connected by its stem 1| with the movable armature 12 of a solenoid 13 which is mounted upon suitable brackets 14 below and in axial alinement with the valve chamber 52. When the solenoid 13 is de-energized the armature 12 and valve 53 are retained in. their uppermost position by means of a coil spring 16 under compression between the armature 12 and a plug 11 in the lower end of the sole-' noid. This solenoid 13 is electrically connected in the circuit which is controlled by the switch 22, as illustrated upon the wiring diagram of Fig. 6. A stop H in the shape of a transverse pin and adapted to abut against the lower open end of the valve chamber 52 limits the upward movement of stem 1|.

The upper end of the valve stem 1I carries a plug 8I of insulating material, and this plug is provided with an annulus 82 of conducting material adapted to establish electrical connection between opposed brush contacts 83 and 84 when the armature 12 and valve 53 are in their upper most position. These contacts 83 and 84 are insulated from the housing so that when the armature 12 is drawn downwards electrical connection between the contacts 83 and 84 is disestablished.

Instead of being connected to the manifold I2 in the conventional manner, the idling outlet 86 from the carburetor I4 through which the idling mixture of fuel flows, leads by a conduit 81 into the interior of the passage 21 below the valve seat 4|, and terminates within a vertical cylinder 88 therein. The interior of the cylinder 88 communicates with the passage 21 through a relatively small port 88, which, however, is adapted to be closed by means of a plunger 8I when the auxiliary air inlet ,valve 42 is moved downwards away from its seat 4I, it being understood that the plunger 8! is rigidly connected to the valve 42 to be actuated thereby. Hence, whenever the auxliiary air inlet valve 42 is moved to open position, it being understood that this occurs only when the butterfly valve I6 of the carburetor is fully closed, the supply of idling fuel also will be completely cut off, and this feature, taken in conjunction with the fact that the relatively high vacuum within the manifold will be relieved by air flowing through the passage 21, serves to prevent the entrance of any fuel whatsoever into the intake manifold when the valve 42 is open.

Referring now to the wiring diagram upon Fig. 6, the generator for the ignition and lighting system of the automobile with which the motor I3 is associated, is indicated at 86. In accordance with conventional practice, one side of the generator 86 is grounded as at 81. The other side of the generator 86 is connected by a conductor 88 to an automatic cut-out 88 of con-- ventional design, which is adapted automatically to open and break the circuit with which it is associated when the current therethrough falls below a predetermined voltage or tends to move in the opposite direction from that in which the currentnorr'nally moves. The only changewhich I have made in the conventional wiring system is to provide an additional cut-cut I8I connected in series with the cut-out 88 so that the current from the generator 86 flows through the two cutouts 88 and IN, thence by a conductor I82 through the ammeter I83, and thence by another conductor I84 to one terminal of a storage battery I86, the other terminal of which is grounded as at I81.

One terminal of the solenoid 13 of'the manifold attachment II is connected by a conductor I88 into the ignition system between the two cutcuts 88 and IN. The other terminal of the solenoid 13 is connected by a conductor I88 to one contact. say the movable contact I8 of the switch 22, whereas the other contact 2| of the switch 22 is grounded as at III.

The ignition system of the motor includes a distributor indicated at II2, one side of which is grounded as at H3, and the other side of which is connected by a conductor 4 to the ignition switch II6 accessible to the operator of the vehicle. However, the brush contacts 83 and 84 are interposed into the conductor II4 so that the distributor head I I2 cannot receive current except when the brushes 83 and 84 are interconnected by the annulus 82.

Preferably, another manually operable switch H1 is interposed in the conductor I88, this switch II1 also being accessible to the operator of the vehicle, so that-he can make the manifold attachment of the present invention either operative or inoperative at will.

Operation Assuming that the switch H1 is closed, and that the motor I3 is operating under working conditions, i. e., under load and with the butterfly valve I6 moved to either partially or fully opened position, the switch 22 will be open, with the result that the solenoid 13 will be de-energized. Hence, the spring 16 will hold the armature 12 and slide valve 53 elevated. Accordingly, communication will be established between the ports 51 and 56, thereby establishing communication between the upper end of the cylinder 46 and the interior of the intake manifold I2. Inasmuch as a partial vacuum exists within the manifold I2 during operation of the motor, this low pressure within the. upper end of the cylinder 46 will permit the pressure of the atmosphere exerted against the lower end of the piston and the spring 48, to force the piston 41 to its upper extreme of movement, thereby pressing the valve 42 onto its seat and preventing the flow of auxiliary air through the passage 21 into the manifold.

It should be explained that the upper end of the valve chamber 52 is in communication with the atmosphere by means of a port I 38 in the valve casing 52 and the lower end of the valve casing 52 is open to the atmosphere at I3l, and. that the valve 53 is short enough to uncover the lower port 58 to the atmosphere at I3I when the upper port 56 is in communication with the middle port 51. Similarly, the upper port 56 communicates with the atmosphere at I38 when the valve 53 is lowered, with the result that atmospheric pressure will be imposed upon the opposite side of the piston 41 from that end of the cylinder 46 which is in communication at any time with the middle port 51.

When the operator of the vehicle wishes to decelerate he closes the butterfly valve I6 by means or the operatingmechanism I8. "This closes the switch 22, whereupon current will flow from the generator 86 through the solenoid 13, thereby developing suillcient electromagnetic force to draw the armature 12 downwards, opening the port 56 to the atmosphere by port I38 and establishing communication between the middle port 51 and the lower port 58. The partial vacuum thus introduced to the under side of the piston 41 will cause it to be forced downwards by the atmospheric pressure against the upper surface thereof, with the result that the auxiliary air inlet valve 42 will be unseated, permitting air to flow from the atmosphere through the passage 21, and thus into the manifold I2, thereby relieving thevacuum within the manifold to such an extent that raw gas is not sucked through the jets of the carburetor, or the butterfly valve may be adjusted so that it does close completely, inasmuch as fuel to operate themotor at idling,

' speed is supplied by way of the conduit 41. and

to the distributor H2 is interrupted. Hence, the

combustion of any residualzcarbureted fuel re-.-

maining" in the the manifold or in the valve chambers of the motor, is prevented, with the result that during the period of deceleration of I the motor any such residual carbureted fuel ispumped out of-the motor, and its place is taken by fresh. pure air which is supplied to the manitold by wayof the passage 21. 1

As soon the period of deceleration is finished. i. e., when the motor hasslowed down to approxi-' mately idling speed,'the cut-outs 99 and IDI will open automatically, thereby dc-energizing the solenoid 13, permitting the valve 53 to return to normal position, whereupon the vacuum of the manifold is againimposed upon the upper side .of the piston 41, which causes the auxiliary air inlet valve 42 again to be seated. This movement of the valve 53 also re-establishes interconnection between the contacts I! and 44, with the result that the distributor H2 is again'energized; and as the valve 42 seats, the idling fuel port 89 is uncovered by withdrawal of the plunger SI,- with the result that sufficient. carbureted fuel is fed to the manifold I2 to keepthe motor operating. at idling speed, even though the butterfly valve I6has not been reopened.

It will be observed that the piston 41 is of considerably greater area than the valve 42. This is to prevent the valve from being opened by atmospheric pressure against its upper surface when the vacuum of the manifold is imposed against its under surface, it being understood that substantially the same pressure exists in the upper portion of the cylinder 4 as that which exists within the manifold. However, when the valve 53 is reversed. the vacuum of the manifold is imposed upon the under sides of both-the valve 42 and the piston 41, resultingjin the im- I mediate opening of the valve 42, whereupon air is permitted to enter the manifold and relieve the vacuum.

It should be explained that the cut-outs II and IIII are so regulated that they automatically open and thereby break the associated circuit when the current therethrough is only slightlyin excess of that which is produced'by the generator 96 when the motor is operating at idling speed. The conductor Ill'which leads tothe solenoid 13 is connected into the'electrical circuit between the two cut-outs S9 and I GI, so that the cut-out 39 will break the circuit to the solenoid 13 from the generator {whereas the other cut-out IlI will break the circuit from the battery I06 to the solenoid 12.

Fig. 7 shows a slightly modified construction,

tion, a pair of terminals I2I and I22 are mounted in the head I23 of the cylinder I24, within which the piston 41 operates. The terminals I2I and I22 are mounted in suitable insulation material I26, and electrical communication is adapted to be established between the two terminals 'I2I and I 22 when a block of insulation I21 carried at the upper end of the valve stem 43 moves upwards and engages a conducting finger I 28 which is pivoted upon the terminal I22, and by continued upward motion .presses the finger I28 in-.

to engagement with a contact I29 carried by the other terminal I2I. An advantage of this construction lies in the fact that it would permit re-establishing the ignition circuit for the motor I3, without requiring that the solenoid .13 be deenergized. Under such an arrangement it would be possible to employ a spring 48 to return the piston 41 to normal] position, whichspring exerts only enough force 1 to return the piston against the partially relieved and reopen the port 89 automatically as soon'as the pressure within the manifolds builds up as a result of the decreased pumping action of the motor, and would not require, that automatic cut-outs be employed to de-energizethe solenoid 13 so as to insure re-establishing the ignition circuit.

It to be understood that the details of the invention as herein disclosed, are subject to alteration within 'the spirit or scope of the appended claims. I

I claim: I I 1. An auxiliary air let for the inlet manifold of an internal combustion engine, compris,- ing a cylinder, a piston reciprocable therein, an

air admissio'nvalve operated by said piston; a. conduit communicating. with said manifold, a

valve adapted to connect said conduit with said cylinder optionally upon either side of" saidpiston, and electromagnetic .means for operating said valve. 1

2. An auxiliary air I inletfor the inlet manifold" of an internal combustionengine. comprising a cylinder, a piston reciproc'able thereim an air admission valve'operated by said piston, a-conduit communicating with saidmanifolma valve adapted to connect said conduit withsaid cylinder optionally upon either side of said piston,

and means p rative when the su l fu l w said manifold is interrupted for" operating said valveI I 3. In combination with the intakemanifold of an internal combustionengine. a carburetor adapted to supplyfu'elto said manifold, a valveadapted to control flow of fuel from said carburetor to said manifold, an auxiliary airjinlet valve for said manifold, means operativewhen said fuel valve is closed for-opening said auxiliary valve, the operationof said opening means being dependent also upon theinrii'ntenance of a'predetermined low pressure said manifold, and means for cutting off the supply of current to the ignition system of said'engine when I said auxiliary valve is open.

4.In combination with the intake manifold of an-internal combustion engine, 'a 'carburetor having a main fuel supply and. an idling fuel supply to said manifold. a fuel valve for .controlling said main fuel supply, an auxiliary air inlet I for-said manifold, means operative when said fuel valve is closed for opening said auxiliary valve, means for interrupting said idling fuel supply when said auxiliary valve is open, means for cutting off the supply of current to the ignition system of said engine when said auxiliary valve is open, and means for closing said auxiliary valve when pressure within said manifold Y builds up to a predetermined minimum.

of said cylinder, means for operating said slide valve, and means operative when said motor is running below a predetermined minimum speed for releasing said slide valve operating means.

6. In a manifold attachment of the class de- I scribed, a housing having a passage therein communicating at one end with the atmosphere and at the other end with the interior of an intake manifold of an internal combustion motor, ,a cylinder having. a piston reciprocable therein, an auxiliary air inlet valve connected to said piston and adapted to open said passage when said piston is lowered, a conduit communicating with the interior of said manifold, a slide valve adapted to connect said conduit optionally with either end of said cylinder, means operative upon cutting off the supply of fuel to said manifold for operating said slide valve, and means operative when said motor is running below a predetermined min- 'imum speed for releasing said slide valve operating means.

7. In a manifold attachment of the class described, a housing having a passage therein communicating at one end with the atmosphere and at the other end with the interior of an intake manifold of an internal combustion motor, a cylinder having a piston reciprocable therein, an

- auxiliary air inlet valve connected to said piston and adapted to open said passage when said piston is lowered, a conduit communicating with the interior of said manifold, a slide valve adapted to connect said conduit optionally with either end of said cylinder, electromagnetic means operative upon cutting oil? the supply of fuel to said manifold for operating said slide valve, and means operative when said motor is running below a predetermined minimum speed for releasing said slide valve operating means.

8. In an attachment for a manifold having a carburetor operably connected thereto, a housing having a passage therein communicating at one end with the atmosphere and at the other end with the interior of an intake manifold of an internal combustion motor, a cylinder having a piston reciprocable therein, an auxiliary air inlet valve connected to said piston'and adapted to open said passage when said piston is lowered, a conduit communicating with the interior of said manifold, a slide valve adapted to connect said conduit optionally with either end of said cylinder, means operative upon closing the fuel supply valve of said carburetor for operating said slide valve to lower said piston, and means operative when said motor is running below a predetermined minimum speed for releasing said slide valve operating means.

ing having a passage therein communicating at one end with the atmosphere and at the other end with the interior of an intake manifold of an internal combustion motor, a cylinder having a piston reciprocable therein, an auxiliary air inlet valve connected to said piston and adapted to open said passage when said piston is lowered, a conduit communicating with the interior of said manifold, a slide valve adapted to connect said conduit optionally with either end of said cylinder, a solenoid having a movable armature connected to said slide valve, a switch adapted to be closed when the fuel supply valve of said carburetor is closed, said switch controlling the supply of current to said solenoid, and means operative when said motor is running below a predetermined minimum speed for releasing said slide valve operating means.

10. In an attachment for a manifold having a carburetor operably connected thereto, a housing having a passage therein communicating at one end with the atmosphere and at the other end with the interior of an intake manifold of an internal combustion motor, a cylinder having a piston reciprocable therein, an auxiliary air inlet valve connected to said piston and adapted to open said passage when said piston is lowered, a conduit communicating with the interior of said manifold, a slide valve adapted to connect said conduit optionally with either end of said cylinder, means operative upon closing the fuel supply valve of said carburetor for operating said slide valve to lower said piston, means operative when said motor is running below a predetermined minimum speed for releasing said a slide valve'operating means, a valve controlling flow of idling fuel from said carburetor to said manifold, and means for closing said idling fuel valve when said auxiliary air valve is open.

11. In an attachment for a manifold having a carburetor operably connected thereto, a housing having a passage therein communicating at one end with the atmosphere and at the other end with the interior of an intake manifold of an internal combustion motor, a cylinder having a piston reciprocable therein, an auxiliary air inlet valveconnected to said piston and adapted to open said passage when said piston is lowered, a conduit communicating with the interior of said manifold, a slide valve adapted to connect said conduit optionally with either end of said cylinder, means operative upon closing the fuel supply valve of said carburetor for operating said slide valve to lower said piston, means operative when said motor is running below a predetermined minimum speed for releasing said slide valve operating means, a valve controlling flow of idlingfuel from said carburetor to said manifold, means for closing said idling fuel valve when said auxiliary air valve is open, and means operative when said auxiliary air valve is open for cutting off the ignition system of said motor.

12. The combination with an intake manifold of an internal combustion engine provided with an electric ignition circuit, a carburetor adapted to supply fuel to the manifold, a throttle valve adapted to control flow of fuel from the carburetor to the manifold, an auxiliary air inlet valve for said manifold, an idling speed fuel supply to said manifold, means to interrupt the idling speed fuel supply when the auxiliary air inlet valve is opened and the speed of the engine is greater than idling speed, means operative when the throttle valve is closed for opening the auxiliary air inlet valve, and means operative when-the auxiliary air inlet valve is opened for opening the ignition circuit. 7

13. The combination with an intake manifold of an internal combustion engine having a genin closed position andthe current in the first circuit exceeds a predetermined voltage and is flowing in one direction, means in said second circuit operative to close said auxiliary air inlet valve when the voltage of the current in the first circuitfall's below a predetermined amount or tends to move in the opposite direction, and an idling fuel supply leading from the carburetor to the manifold and operative when the. throttle valve is closed and the speed of the engine is at a predetermined minimum.

engine is at a predetermined minimum.

14. The combination with an intalre manifold of an internal combustion engine having a generator and a storage battery connected in circuit, a carburetoradapted-to supply fuel to said manifold, a throttle valve'adapted to controlflow of fuel from the carburetor to said manifold, an auxiliary air inlet valve for said manifold, a

pair of spaced-cutouts in the circuit connecting. I

the generator with the storage battery, a second electric circuit leading-from the first circuit at a point between the two 'icutouts, means in said second circuit to open said-auxiliary air inlet l valve when. thethrottle valve'is in closed position and the current in the'iirst circuit'exceedsfa predeterminedvfoltage and is flowing in one direc-f tion, means in said second circuit operatives-to close said auxiliary air inlet valve when the voltage of the current in the first circuit falls below.

a predetermined amount or tends to move in the opposite direction, and an idling fuel supply leading from the carburetor'to said manifold and operatedby saidvauxilia'ry air'inlet'valve when-the throttle valve is closed-and the speed of ;the'

w. nonamq'. 

